Question 1

Which of the following is the final electron acceptor in the electron transport chain during aerobic respiration in eukaryotes?

Accepted Answer

Oxygen ($$O_2)$$

Question 2

In prokaryotes, where is the electron transport chain (ETC) located?

Accepted Answer

In the cytoplasmic membrane

Question 3

Which category of carrier molecules in the electron transport chain contains iron and is involved in electron transfer?

Accepted Answer

Cytochromes

Question 4

What is the main purpose of pumping protons ($$H^+) $$across the membrane during electron transport?

Accepted Answer

To create a proton motive force for ATP synthesis

Question 5

Which process is responsible for the majority of ATP production in aerobic respiration?

Accepted Answer

Chemiosmosis (oxidative phosphorylation)

Question 6

During anaerobic respiration in Escherichia coli, which molecule acts as the final electron acceptor?

Accepted Answer

Nitrate ion ($$NO_3$$^-$$)

Question 7

Which of the following statements about fermentation is TRUE?

Accepted Answer

Fermentation uses an organic molecule as the final electron acceptor.

Question 8

In lactic acid fermentation, which molecule is reduced to form lactic acid?

Accepted Answer

Pyruvic acid

Question 9

How many ATP molecules are typically produced from one molecule of NADH during oxidative phosphorylation?

Accepted Answer

3 ATP

Question 10

Which enzyme is responsible for synthesizing ATP using the proton motive force?

Accepted Answer

ATP synthase

Question 11

Which metabolic pathway is shared by both respiration and fermentation?

Accepted Answer

Glycolysis

Question 12

During alcoholic fermentation by Saccharomyces cerevisiae, what is the final electron acceptor?

Accepted Answer

Acetaldehyde

Question 13

Which process converts fatty acids into two-carbon units for entry into the TCA cycle?

Accepted Answer

Beta-oxidation

Question 14

What is the role of deamination in protein catabolism?

Accepted Answer

It removes amino groups from amino acids, allowing them to enter metabolic pathways.

Question 15

Which of the following is TRUE regarding the ATP yield from FADH$$_2$$ compared to NADH during oxidative phosphorylation?

Accepted Answer

FADH$$_2$$ yields fewer ATP because it activates fewer proton pumps.

Question 16

Which of the following is NOT a carrier molecule in the electron transport chain?

Accepted Answer

ATP synthase

Question 17

A patient is diagnosed with a genetic defect in cytochrome proteins. Which cellular process would be most directly affected?

Accepted Answer

Electron transport chain

Question 18

Which of the following best describes chemiosmosis?

Accepted Answer

The use of a proton gradient to drive ATP synthesis

Question 19

Which metabolic process is most likely to occur in a methanogen using carbonate ($$CO_3$$^{2-}$$) as the final electron acceptor?

Accepted Answer

Anaerobic respiration

Question 20

Which of the following is a correct sequence of events in aerobic glucose catabolism?

Accepted Answer

Glycolysis → TCA cycle → Electron transport chain

Microbial Metabolism: Electron Transport, Chemiosmosis, and ATP Yield

Study Guide - Practice Questions